Surgeons have traditionally depended on external illumination from the operating room light and adequate exposure to obtain a good surgical view. This often requires large incisions, to provide access for the operation. The introduction of fiber optics in modern endoscopes has allowed surgeons to see clearly with good illumination inside a bodily cavity without having to make a big incision. Minimally Invasive Surgery (MIS) has now replaced most conventional open surgical operations. Computer-assisted or robotic technology has contributed further to the development of MIS as the computer sensors of the robotic machine can reliably and delicately translate the movements of the surgeon's fingers and wrists into movements of the slave laparoscopic instruments inside the body cavities. These developments have allowed good dexterity and precision control of surgical instruments for fine reconstructive surgery in a small confined space.
However, the MIS approach requires multiple incisions for the insertion of the camera and various laparoscopic instruments. Over the past few years, Laparo-Endoscopic Single-Site (LESS) surgery technologies have become available, but these suffer immensely from a lack of proper triangulation between the camera and the working instruments, which is important for good operative ergonomics and hence ease and success of surgery.
Natural orifice translumenal endoscopic surgery (NOTES) is an alternative to open abdominal surgery that uses endoscopic techniques with a view to completely avoid the need for external abdominal wall incisions. Theoretically, NOTES offers advantages by minimizing access trauma and the various complications associated with external incisions including wound infections, pain, hernia formation, unsightly abdominal scars and adhesions.
However, the NOTES approach suffers from significant drawbacks including inadequacy of proper triangulation of surgical instruments and hence poor working ergonomics, an inability to apply off-axis forces, and difficulties in passing multiple instruments into the abdominal cavity for proper surgical manipulations.